Portable or mobile devices originally introduced as mobile phones or electronic agendas become more and more ubiquitous. As the processing power of their internal processors grows and equally the bandwidth for communication with stationary processors, such portable devices take on more and more the role of multi-purpose tools available to consumers and specialist users alike.
It has been recognized that portable devices can benefit from the presence of sensors capable of providing chemical analysis of materials brought into contact or the vicinity of the device. Whilst there are many possible applications for such sensors, it suffices to consider for example the analysis of air surrounding the portable device. Such an analysis can be useful for multiple purposes such as testing for hazardous gases, breath analysis for general medical purposes or driving fitness, and the like.
It has been known to incorporate gas sensors into portable sensor devices, such as mobile phones or tablet computers. For example, humidity sensors have been incorporated into some smartphone devices. However, humidity (i.e. gaseous water in air) is only one gas that might be of interest to a user of this type of device. Therefore, there is a need to provide devices that allow for measuring of a larger selection of gases, such as alcohol, CO, benzene, or groups of gases, which can e.g. be classified as certain smells or odors.
In case such gases can cause a hazard or pose an otherwise relevant condition for the user, it is desirable to use portable devices with integrated chemical sensors to issue an alarm or a notification to its user, to the surrounding of the user or to a remote location or to trigger an automated response.
As the issuing of a false hazard alarm or the triggering of an automated response can be disruptive and costly, it is seen as an object of the invention to improve the reliability of an alert system based on the use of portable devices with an integrated chemical sensor.